Improve cloning performance for large numbers of clones (LP: #1567557)

[mirror_zfs-debian.git] / config / kernel-truncate-setsize.m4

diff --git a/config/kernel-truncate-setsize.m4 b/config/kernel-truncate-setsize.m4
index d8b2b47bd7de4007dead8d1548206290bd0b6a54..7e4aff479a90e0952888191c55eabd51a6bddc3e 100644 (file)
--- a/config/kernel-truncate-setsize.m4
+++ b/config/kernel-truncate-setsize.m4
@@ -2,11 +2,17 @@ dnl #
 dnl # 2.6.35 API change
 dnl # Added truncate_setsize() helper function.
 dnl #
-AC_DEFUN([ZFS_AC_KERNEL_TRUNCATE_SETSIZE], [
-       ZFS_CHECK_SYMBOL_EXPORT(
-               [truncate_setsize],
-               [mm/truncate.c],
-               [AC_DEFINE(HAVE_TRUNCATE_SETSIZE, 1,
-               [truncate_setsize() is available])],
-               [])
+AC_DEFUN([ZFS_AC_KERNEL_TRUNCATE_SETSIZE],
+       [AC_MSG_CHECKING([whether truncate_setsize() is available])
+       ZFS_LINUX_TRY_COMPILE_SYMBOL([
+               #include <linux/mm.h>
+       ], [
+               truncate_setsize(NULL, 0);
+       ], [truncate_setsize], [mm/truncate.c], [
+               AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_TRUNCATE_SETSIZE, 1,
+                         [truncate_setsize() is available])
+       ], [
+               AC_MSG_RESULT(no)
+       ])
 ])